It is previously known to use a hacksaw blade as a keyhole saw where there is limited space, as when sawing narrow slits, for cutting nails between wooden members, and for clearing screwdriver slots on screws.
The hacksaw blade is then not held in tension with help of the holes at its ends, but its rear part is inserted in a longitudinal recess or a series of recesses in the gripping part of a handle, which at least partly encloses this part of the blade, and has basically the direction of the blade. The recess has a narrow flat section to prevent rotation of the blade.
In some previous art, the handle has a finger-like forward extension, which can grip the blade near the middle as in West U.S. Pat. No. 3,756,298, with the aim of having at least the part below this extension rigidly supported.
The blade is usually clamped to the handle with a screw, and most previously known designs have screws with horizontal axis, located in the gripping part or in its forward extension. In the former case, the front part of the blade is inadequately guided, even if there is a grooved forward extension, because this does not exert any force on the blade. In the latter case, the screw will through its size make it more difficult to saw in narrow spaces, and there is a great risk of the screw getting loose by striking the sawn object. In the present invention, those and other drawbacks have been eliminated through a new design of the holder, which enables it to hold the blade steadier than previous designs.